Association between telomere length in the DNA of peripheral blood leukocytes and the propofol dose in anesthesia induction: an observational study

Abstract Introduction: Propofol is a widely used anesthetic and its dose is closely related to aging. Telomere length (TL) is a unique heritable trait, and emerging as a biomarker of aging, health and disease. Telomerase RNA component (TERC) plays an important role in maintaining TL. We proposed a hypothesis that propofol dose in general anesthesia can be predicted by measuring TL before operation, which greatly reduced the risk of anesthesia, especially the elderly. Methods: The association between the propofol dose in anesthesia induction and: TL in the DNA of peripheral blood leukocytes; body weight; sex; difference of the Bispectral Index (BIS) before and after anesthesia induction in patients was evaluated by multivariable linear regression analyses. The mutation at the 5'end or 3'end of TERC was detected. We recruited 100 patients of elective surgery. Results: We found that propofol dose in anesthesia induction was clearly correlated significantly with TL (r = 0.78, p < 0.001), body weight (r = 0.84, p = 0.004), sex (r = 0.83, p= 0.84, p = 0.004), sex (r = 0.83, p = 0.004), and difference of BIS before and after anesthesia induction (r = 0.85, p = 0.029). By comparing the absolute values of standardized regression coefficients (0.58, 0.21, 0.19, and 0.12) of the four variables, it can be seen that TL contributes the most to the propofol dose in anesthesia induction. However, the mutation at the 5' end or 3' end of TERC was not found. Conclusions: These findings provide preliminary evidence that the propofol dose in anesthesia induction was clearly correlated with genetically determined TL. TL may be a promising predictor of the propofol dose, which is beneficial to improve the safety of anesthesia and reduce perioperative complications.

Relationship between Post-operative Cognitive Function Decline and Dose of General Anesthetic Propofol in the Elderly / 中国康复理论与实践

@#Objective To explore the relationship between post-operative cognitive dysfunction (POCD) and the dose of general anesthetic propofol in the elderly. Methods 96 patients undergoing thoracic operation were selected and randomly assigned to high bispectral index (BIS) value (HIBIS 50~60, low dose of propofol) and low BIS value (LOBIS 30~40, high dose of propofol). Remifentanyl was infused in both group with the dose of 0.2 μg/kg ⋅ min. The dose of propofol was adjusted with target-controlled infuse (TCI) according to the different ranges of BIS value in different groups. The mean arterial pressure was maintained in a certain level. The dose of propofol was recorded during the operation. Cognitive function was assessed by 12 neurophysiological tests recommended by International Study of Post Operative Cognitive Dysfunction (ISPOCD) on the day before operation and the 7th day after operation. And the D-value of the tests before and after the operation was calculated. Results 47 cases in the HIBIS group and 45 cases in the LOBIS group were included in the end. The incidences of POCD were 6.3%(3 cases) and 2.2%(1 case) respectively in HIBIS group and LOBIS group according to Mini-Mental State Examination (MMSE) score, and 12.8% (6 cases) and 6.7% (3 cases) according to combination judgment, but there was no significantly difference (P>0.05). The post-operative scores were significantly lower than pre-operative scores (P<0.01) on Hopkins Verbal Learning Test-Revised (HVLT-R) in HIBIS group. and HVLT-R dealyed Recall Test, Hvlt- r Recognition Discrimination Index and Verbal Fluency Test in both groups (P<0.01), including verbal and words. The D-values of 4 neurophysiological tests were higher in the HIBIS group than in the LOBIS group. The dose of propofol was significantly lower in the HIBIS group than in the LOBIS group (P<0.01). Conclusion As the same level of analgisia and hemodynamics, the more the dose of propofol is, the better the post-operative function is in the elderly.